I 131 uptake test

n.

A test of thyroid function in which iodine-131 is given orally and 24 hours later the amount present in the thyroid gland is measured and compared with normal levels.

The American Heritage® Stedman's Medical Dictionary Copyright © 2002, 2001, 1995 by Houghton Mifflin Company. Published by Houghton Mifflin Company.